Assume the speed of sound is 343 m/s. You are sitting 150 m away from home plate at a baseball game. How much time in seconds elapses between the batter hitting a home run and the moment you actually hear the batter hitting the ball

  t = 0.437 s

Explanation:

Sound is a wave so its speed is constant

         v = x / t

         t = x / v

indicates that the distance is x = 150 m

         t = 150/343

         t = 0.437 s

this is the time it takes to hear the hit

To see the blow it is almost instantaneous since the speed of light is much greater c = 3 10⁸ m / s

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg